'random' order of radio buttons?

matthewstafford

Hello,

Does anyone have a good idea how to make the order that radio buttons appear on a page 'random'?

I have a form for a quiz that has five radio buttons with one correct answer and four incorrect answers against them. The answers are pulled from my database and at the minute all come through in the same order (i.e. where I put them against the 'value') so when the user submits and the next question, with its answers, are pulled from the database they are in the same order as the previous answers.

What I'd like is to use the same page and same form, but when the answers are pulled from the database they go against the radio buttons randomly (or at least in a few different orders that can't be predicted).

Any ideas how this could be done with handy php code?

Many thanks,

Matthew

devinemke

to randomly pull records from the table do:

SELECT * FROM table ORDER BY RAND()

depending on the logic of your app it may be easier to do the random sorting in PHP using [man]array_rand[/man] or [man]shuffle[/man]

matthewstafford

Thanks devinemkw,

A snippet from my form is:

  <input type="radio" name="radQ1" value="<?php echo $row['correctanswer']; ?>"     /><?php echo $row['correctanswer'];    ?><br></br>
  <input type="radio" name="radQ1" value="<?php echo $row['incorrectanswer1']; ?>"  /><?php echo $row['incorrectanswer1']; ?><br></br>
  <input type="radio" name="radQ1" value="<?php echo $row['incorrectanswer2']; ?>"  /><?php echo $row['incorrectanswer2']; ?><br></br>
  <input type="radio" name="radQ1" value="<?php echo $row['incorrectanswer3']; ?>"  /><?php echo $row['incorrectanswer3']; ?><br></br>
  <input type="radio" name="radQ1" value="<?php echo $row['incorrectanswer4']; ?>"  /><?php echo $row['incorrectanswer4']; ?><br></br>

So the $row['whatever'] is pulled from the database, but even if I do the random SELECT it'll still be against the first radio button. I'd like to have the correct answer against a different radio button for each question so the examinee can't predict where it'll be.

Do you or anyone else know if it's possible to have, say, 5 forms in html but have some kind of 'case' statement so that, depending on the case number, only one form will be displayed on the page. (I'd have a random number to determine the case).

Thanks again,

Matthew

devinemke

this will probably open up a big can of worms here but i would suggest a very different data structure.

2 tables: questions and answers

questions
question_id (INT) PK
text (VARCHAR)

answers
answer_id (INT) PK
question_id (INT)
text (VARCHAR)
correct (BOOL) true for correct / false for incorrect

sample code for getting the Q&A's (assuming mySQL):

<?php
// connect to db here

$result = mysql_query('SELECT * FROM questions ORDER BY question_id') or exit(mysql_error());
while ($row = mysql_fetch_assoc($result)) {$questions[$row['question_id']] = $row['text'];}

$result = mysql_query('SELECT * FROM answers ORDER BY RAND()') or exit(mysql_error());
while ($row = mysql_fetch_assoc($result)) {$answers[$row['question_id']][$row['answer_id']] = $row['text'];}

echo '<form action="" method="POST">';

foreach ($questions as $key => $value)
{
	echo 'Q: ' . $value['text'] . '<br>';
	foreach ($answers[$key] as $subkey => $subvalue)
	{
		echo '<input type="radio" name="answers[' . $key . ']" value="' . $subkey . '">' . $subvalue . '<br>';
	}
	echo '<hr>';
}

echo '
<input type="submit" name="submit" value="submit">
</form>
';
?>

then in your form processing code you will have an array called $_POST['answers'] with the question_id's as the keys and the answers_id's as the values. you just then need to query the db to see if the answers are correct.

matthewstafford

Thanks devinemke, you've solved my problem with this one.

What I've done is take your first suggestion and selected from the database, put the answers into an array, shuffled the array then assigned the keys to the radio buttons.

Once the examinee selects a radio button and submits I can compare their answer to the correct answer.

You've really helped me out, many thanks agian.

Matthew